Part of the indoor pool, which perches atop the 24-story hotel, protrudes from the main building and is suspended mid-air. Its bottom is constructed with toughened glass.

This gives guests a delirious sense of swimming in the sky -- they can see the street clearly down below while passers-by on Xiuyan Lu can see the swimmers way up above.

"I felt as if I was flying in the sky -- I could also enjoy the beautiful scenery of Pudong from here ... it's so cool and wonderful," a swimmer told CCTV.

"We wanted to provide our guests a unique swimming experience, and let them feel they're vacationing even in a bustling city," said a spokesperson from InterContinental Hotels Group, parent company of Holiday Inn.

Most of the pool at Holiday Inn Shanghai Pudong Kangqiao is indoors, without the overhang.

While not splashing in the water, guests can enjoy Pudong urban views stretching as far as the Lujiazui skyline at the poolside lounge.

Exactly 30 meters long (about 98 feet), six meters wide (20 feet) and 1.5 meters deep (5 feet), the swimming pool is the first of its kind in China. It was designed by Singaporean firm Chan Sau Yan Associates, which helmed the interior design of the four-star hotel.

The Holiday Inn Shanghai branch said it gathered input from various architects and even aerospace experts while constructing this sky-high glass-bottomed water container to ensure its safety.

The 390-room, four-star hotel -- which opened in May 2011, is located in the booming suburb of Kangqiao, which is some 22 kilometers southeast from Shanghai downtown and 30 kilometers west of Shanghai Pudong International Airport.

According to the staff working at the hotel's gym, the swimming pool is open to hotel guests and a limited number of health club members.